S7-300 Memory Cards -- Product information -- Technical data
This entry describes how to work with Micro
Memory Cards (MMC). A sample project is also included in Point 4. The
program shows how you can check whether specific data in a data block
is located in the load memory.
1. How should I save blocks or configuration data on the MMC which are transferred online to the CPU?
When you load blocks (OB, FC, FB, DB) and system data (from the
HW Config among other places, for example) into the CPU, they are automatically saved in such a way as to be safeguarded against voltage failure. The MMC is a flash EPROM medium.
2. Is there still need for the "Copy RAM to ROM..." function?
Not for saving blocks. However, if you have changed data blocks,
for instance if you have optimized control parameters, this function
also allows you to save the changed data values on the MMC (i.e. on the
load memory), which means that these new values are also available
following general PLC resetting (including in cases where the MMCs are
used as spare parts in another CPU).
Please note carefully that the "Copy RAM to
ROM..." function affects all data blocks that are identified as
"unlinked". In the case of these data blocks, when the "Copy RAM to
ROM..." function is performed, the initial values in the load memory
(on the MMC) are overwritten with the actual values in the main memory.
For all data blocks, the initial values are taken as new values after
an overall reset. In the case of non-remanent data blocks the initial
values are also taken as new values after POWER OFF/ON or after
STOP/RUN operating modes.
If you want to save individual data blocks or data block
elements in the load memory, you can use SFC84 to do that. Here, please
note the following Point 3.
3. Can I save data blocks on the MMC via the user program, i.e. use the content as new initial values in the load memory?
CPUs with MMCs feature the SFCs 82, 83 and 84 for this purpose:
- SFC82 allows you to set up a data block in the load memory.
- SFC83 allows you to copy data areas from the load memory to the main memory, and
- SFC84 saves data areas in the load memory, i.e. it performs
the function which is formulated in the question. However, bear in mind
that the MMCs support a limited number of writing cycles (according to
the manufacturer's details, 100,000 writing cycles are possible). For
details about the memory concept of CPUs (load memory, main memory...
), please refer to the FAQ in Entry ID 7302326.
4. How can I check whether the data is really saved in the load memory with SFC84?
A check is possible if the data block is declared as "unlinked".
After copying an "unlinked" DB with SFC83 to the working area of
another DB you can make a check. In the load memory itself it is not
possible to access with a variables table or via "Monitor/control
variable", because access is made here to the working area. There is an
example of how to work with SFC83 attached. This illustrates how the
SFC 84 works.
Please also bear in mind that SFC 83 and SFC 84 work asynchronously.
This means that the SFCs might need several cycles to complete a job.
If the data block in the load memory has the attribute "unlinked", you
can make the check by loading the DB into the PG. Here, STEP 7
retrieves the current values from the load memory during each loading
process. In this regard, also refer to the FAQ in Entry ID 21688777.
Save the "MMC_S7_300_SFC83.zip" file
in a separate directory and then dearchive it. The S7 project then
unpacks with all the associated subdirectories. You can use the SIMATIC
Manager to open and process the extracted project.
MMC_S7_300_SFC83.zip ( 158 KB )
The sample program is freeware. Any user
can use, copy and forward this program FREE OF CHARGE. The authors and
owners of this program take no responsibility whatsoever for the
functionality and compatibility of this software. Use of the software
is at the user's own risk. Since this software is free of charge, there
is no warranty nor entitlement to error correction and hotline support.
5. When is it useful to compress an S7-300 CPU with MMC?
Deleting blocks on the CPU creates gaps in the load and main
memories. The gaps are not automatically closed when new or changed
blocks are transferred. When you compress, the gaps are closed by
copying the existing or new blocks. The procedure is comparable with
the defragmenting of hard disks in Windows.
You reduce cycle times
by compressing. That is why it is only useful to compress in order to
close a large number of gaps after blocks have been deleted frequently
in the CPU.
Compressing just after performing the "Load user program onto memory card" function is not
useful, because the MMC is deleted when the function is performed and
the blocks can be transferred without any gaps onto the MMC.
Compressing, transferring and deleting blocks extends the cycle time of the CPU.
In the STOP operating mode you can perform compressing completely. In
the RUN-P operating mode, blocks that are open because of the running
program cannot be moved when compressing is performed.
Which memory cards can you use with a S7-300 CPU?
The following tables (Table 01 to Table 08) show the S7-300 CPUs and the memory cards to be used with them.
Here we distinguish between:
- MC (Memory Card)
- MMC (Micro Memory Card)
|CPU 312||Order no.||Type of Memory Card|
|CPU 312||6ES7 312-1AD10-0AB0||MMC max. 4MB|
|6ES 7 312-1AE13-0AB0||MMC max. 4MB|
|CPU 312C||6ES7 312-5BD00-0AB0||MMC max. 4MB|
|6ES7 312-5BD01-0AB0||MMC max. 4MB|
|6ES7 312-5BE03-0AB0||MMC max. 4MB|
|CPU 312 IFM||6ES7 312-5AC02-0AB0||No Memory Card|
|6ES7 312-5AC82-0AB0||No Memory Card|
|CPU 313||Order no.||Type of Memory Card|
|CPU 313||6ES7 313-1AD02-0AB0||MC max. 512KB|
|6ES7 313-1AD03-0AB0||MC max. 4MB|
|CPU 313C||6ES7 313-5BE00-0AB0||MMC max. 4MB|
|6ES7 313-5BE01-0AB0||MMC max. 8MB|
|6ES7 313-5BF03-0AB0||MMC max. 8MB|
|CPU 313C-2 DP||6ES7 313-6CE00-0AB0||MMC max. 4MB|
|6ES7 313-6CE01-0AB0||MMC max. 8MB|
|6ES7 313-6CF03-0AB0||MMC max. 8MB|
|CPU 313C-2 PtP||6ES7 313-6BE00-0AB0||MMC max. 4MB|
|6ES7 313-6BE01-0AB0||MMC max. 8MB|
|6ES7 313-6BF03-0AB0||MMC max. 8MB|
|CPU 314||Order no.||Type of Memory Card|
|CPU 314||6ES7 314-1AE03-0AB0||MC max. 512KB|
|6ES7 314-1AE04-0AB0||MC max. 4MB|
|6ES7 314-1AE83-0AB0||MC max. 512KB|
|6ES7 314-1AE84-0AB0||MC max. 4MB|
|6ES7 314-1AF10-0AB0||MMC max. 8MB|
|6ES7 314-1AF11-0AB0||MMC max. 8MB|
|6ES7 314-1AG13-0AB0||MMC max. 8MB|
|6ES7 314-5AE03-0AB0||No Memory Card|
|6ES7 314-5AE10-0AB0||MC max. 4MB|
|6ES7 314-5AE83-0AB0||No Memory Card|
|CPU 314C-2 DP||6ES7 314-6CF00-0AB0||MMC max. 4MB|
|6ES7 314-6CF01-0AB0||MMC max. 8MB|
|6ES7 314-6CF02-0AB0||MMC max. 8MB|
|6ES7 314-6CG03-0AB0||MMC max. 8MB|
|CPU 314C-2 PtP||6ES7 314-6BF00-0AB0||MMC max. 4MB|
|6ES7 314-6BF01-0AB0||MMC max. 8MB|
|6ES7 314-6BF02-0AB0||MMC max. 8MB|
|6ES7 314-6BG03-0AB0||MMC max. 8MB|
|CPU 315||Order no.||Type of Memory Card|
|CPU 315||6ES7315-1AF02-0AB0||MC max. 512KB|
|6ES7 315-1AF03-0AB0||MC max. 4MB|
|CPU 315-2 DP||6ES7 315-2AF02-0AB0||MC max. 512KB|
|6ES7 315-2AF03-0AB0||MC max. 4MB|
|6ES7 315-2AF82-0AB0||MC max. 512KB|
|6ES7 315-2AF83-0AB0||MC max. 4MB|
|6ES7 315-2AG10-0AB0||MMC max. 8MB|
|CPU 315-2 PN/DP||6ES7 315-2EG10-0AB0||MMC max. 8MB|
|6ES7 315-2EH13-0AB0||MMC max. 8MB|
|CPU 315F-2 DP||6ES7 315-6FF01-0AB0||MMC max. 8MB|
|CPU 315F-2 PN/DP||6ES7 315-2FH10-0AB0||MMC max. 8MB|
|6ES7315-2FH13-0AB0||MMC max. 8MB|
|CPU 315T-2 DP||6ES7 315-6TG10-0AB0||MMC min. 4MB, max. 8MB|
|6ES7 315-6TH13-0AB0||MMC min. 4MB, max. 8MB|
|CPU 316||Order no.||Type of Memory Card|
|CPU 316||6ES7 316-1AG00-0AB0||MC max. 512KB|
|CPU 316-2DP||6ES7 316-2AG00-0AB0||MC max. 4MB|
|CPU 317||Order no.||Type of Memory Card|
|CPU 317-2 DP||6ES7 317-2AJ10-0AB0||MMC max. 8MB|
|CPU 317-2 PN/DP||6ES7 317-2EJ10-0AB0||MMC max. 8MB|
|6ES7 317-2EK13-0AB0||MMC max. 8MB|
|CPU 317F-2 DP||6ES7 317-6FF00-0AB0||MMC max. 8MB|
|6ES7 317-6FF03-0AB0||MMC max. 8MB|
|CPU 317F-2 PN/DP||6ES7 317-2FJ10-0AB0||MMC max. 8MB|
|6ES7 317-2FK13-0AB0||MMC max. 8MB|
|CPU 317T-2 DP||6ES7 317-6TJ10-0AB0||MMC min. 4MB, max. 8MB|
|6ES7 317-6TK13-0AB0||MMC min. 4MB, max. 8MB|
|CPU 318||Order no.||Type of Memory Card|
|CPU 318-2||6ES7 318-2AJ00-0AB0||MC max. 4MB|
If you are doing an update of the operating system for the S7-318-2 CPU, you can use S7-400 memory cards, order number 6ES7952-1K... For details, please see Entry ID: 7286150.
|CPU 319||Order no.||Type of Memory Card|
|CPU 319-3 PN/DP||6ES7 318-3EL00-0AB0||MMC max. 8MB|
|CPU 319F-3 PN/DP||6ES7 318-3FL00-0AB0||MMC max. 8MB|
List of Memory Cards (MC):
In normal mode, only the "short" memory cards (MC) can be used with S7-300 CPUs (with MC slot). Table 09 lists the order numbers of these memory cards.
|Memory Card FEPROM 16 KB||6ES7 951-0KD00-0AA0|
|Memory Card FEPROM 32 KB||6ES7 951-0KE00-0AA0|
|Memory Card FEPROM 64 KB||6ES7 951-0KF00-0AA0|
|Memory Card FEPROM 128 KB||6ES7 951-0KG00-0AA0|
|Memory Card FEPROM 256 KB||6ES7 951-1KH00-0AA0|
|Memory Card FEPROM 512 KB||6ES7 951-0KJ00-0AA0|
|Memory Card FEPROM 1 MB||6ES7 951-1KK00-0AA0|
|Memory Card FEPROM 2 MB||6ES7 951-1KL00-0AA0|
|Memory Card FEPROM 4 MB||6ES7 951-1KM00-0AA0|
|Memory Card FEPROM 16 KB*||6ES7 951-0KD80-0AA0|
|Memory Card FEPROM 32 KB*||6ES7 951-0KE80-0AA0|
|Memory Card FEPROM 64 KB*||6ES7 951-0KF80-0AA0|
|Memory Card RAM 128 KB||6ES7 951-0AG00-0AA0|
|Memory Card RAM 256 KB||6ES7 951-1AH00-0AA0|
|Memory Card RAM 512 KB||6ES7 951-1AJ00-0AA0|
|Memory Card RAM 1 MB||6ES7 951-1AK00-0AA0|
|Memory Card RAM 2 MB||6ES7 951-1AL00-0AA0|
* These memory cards are designed for use in the extended temperature range.
More information is available in the manual "SIMATIC Automation System S7-300, CPU Data, CPUs 312IFM to 318-2 DP", sections 1.1.4 and 4.2 in Entry ID: 8860591.
List of Micro Memory Cards (MMC):
Table 10 lists the order numbers of the Micro Memory Cards (MMC).
|Micro Memory Card 64 KB||6ES7 953-8LF20-0AA0|
|Micro Memory Card 128 KB||6ES7 953-8LG11-0AA0|
|Micro Memory Card 512 KB||6ES7 953-8LJ20-0AA0|
|Micro Memory Card 2 MB||6ES7 953-8LL20-0AA0|
|Micro Memory Card 4 MB||6ES7 953-8LM20-0AA0|
|Micro Memory Card 8 MB||6ES7 953-8LP20-0AA0|